Carburetor



Aug; 23, 1932. o, BALL ET AL 1,873,919

CARBURETOR Filed May 51. 1950 2 sheets-sheet 1 I/ I I //)'//7\ VENTORFREDERICK a. .fX/JL AND BY THO/HA6 M. BALL.

ATTORNEY Aug. 23, 1932. F. 0. BALL ET AL CARBURETOR Filed May 31, 1.9502 Sheets-Sheet INVENTOR FREDERICK 0. BALL.

THOMAS M- L BY BA L.

27 7 ATTORNEY I WM 1 Patented Aug. 23, 1932 UNITED STATES PATENT; OFFICEFREDERICK 0. BALL AND THOMAS M. BALL, DETROIT, MICHIGAN CARIBURETOBApplication filed May 81,

This invention relates to carburetor fuel feeding apparatus andparticularly to 1mproved means for introducing a plck-up shot into thefuel mixture system of an internal combustion engine.

Heretofore, in carburetors of the type which have a separate circuit forfeeding a temporary discharge of fuel (called a pickup shot) from areservoir or from any other source, into the fuel mixture system of anengine thereof, it has been the practice to employ either a mechanicallycontrolled or a vacuum controlled .pump in the pick-up system. Pumps ofthis kind generally commu- '15 nicate with the fuel mixture systemthrough a passage from which the fuel is either drained by gravity orevaporated by suction between operations of the pump or WlllCh is closedby a check valve past which the suction tends to draw the fuel at highvacuum stages. With this arrangement a substantial portion of thepick-up passage is emptied after each pick-up shot is discharged andmust be filled by a succeeding pick-up shot before any fuel isintroduced into the fuel mixture system.

The temporary discharge of fuel provided by the pick-up shot is requiredimmedlately after the throttle is opened from a relatively closedposition The preliminary filling of the pick-up passage delays thetemporary discharge causing the fuel mixture to be excessively leanimmediately after the throttle is opened, at which stage of the engineoperation a rich fuel mixture is particularly needed.

The main objects of the invention are to provide a pick-up system whichhas a fuel passage that is at all times filled with fuel substantiallyto the outlet thereof so as to discharge fuel into the fuel mixturesystem of an-engine immediately upon actuation of a pick-up pump; toprovide an improved valve in the fuel passage ofa pick-up system forsealing the passage near its outlet end, after each pick-up shot isdischarged into the fuel mixture system; and to provide a valve of thiskind which is opened by'the pressure exerted on the fluid in the passagewhen the to pump is actuated and on which the vacuum 1980. Serial No.458,567.

of the fuel mixture system has a closing effect. 7

Further objects of this invention are to provide a valve structure forthe discharge end of a pick-up system whichma'y be conveniently builtinto the structure 'ofa carburetor and which may also be constructed asa separate unit if desired, and applied to any part of the fuel mixturesystem of an engine, as forexample to the manifold thereof.

An illustrative embodiment of our invention is shown in the accompanyingdrawings, in which:

Fig. 1 is a central vertical section of an updraft carburetor embodyingour invention.

Fig. 2 is. a central vertical section of a down-draftcarbliretor havinga pick-up system which embodies 'our invention.

Fig. 3 is afragmentary side elevation, part- I ly in section, includinga carburetor and an o intake manifold in connection with which isillustrated a modified form of our invention.

Fig. 4 is a fragmentary vertical section of an intake manifold inconnection with which, a further development of our invention isillustrated.

In the form shown in Fig. 1, the improved pick-up system is illustratedin connection with a carburetor of the up-draft t pewhich includes abody part having a fue reservoir 1, mixing chamber 2 and inlet born 3. Journaled in apertures in the walls of the mixing chamber 2 is a shaft 4on which a throttle valve 5 is mounted. The reservoir 1 is provided witha fuel inlet6 which has a valve seat 7 against which a valve 8 isreleasably held by fuel level regulating means comprising a float 9having an arm 10 pivotally mounted at 11 on a bracket 12 of thereservoir N cover 13. A fuel passage 14 communicates to at one end withthe interior of the reservoir 1 and at its other end with a fuel nozzle15 located in the interior of the mixing chamher and having an outletorifice 16 slightlyabove the fuel level 17 of the reservoir.

Formed in the interior of the-reservoir 1 is a cylinder 18 having aninlet 19 communicating with the fuel passage 14. The upper end of theinlet 19 has a valve seat 20. on which a ball valve 21 is seated.Slidably mounted in and piston 22 form a pick-up pump for temporarilyfeeding a supply of fuel of a predeterm ned quantity to the interior ofthe mixing chamber substantially independent of the suction therein.

Formed in the body part of the carburetor is a passage 28 having aninlet 29 communicating with the interior of the cylinder 18 chamber 30which is also provided in the body part of the carburetor, the fuelpassage 28 being located below the fuel level 17 of the reservoir. Thevalve chamber 30 has an outlet 31 at its upper end in which a nozzle '32extending into the interior' of the mixing chamber 2 is mounted. Formedat the lower end of the valve chamber 30 is a drain pasextremity of theenlarged portion 37 and the inner end of a hollow ug 40 which isthreaded in the lower end 0 the valve housing.

The pick-up pump is provided with actuatin mechanism including a bellcrank lever 41, xed on the throttle shaft 4 by a pin 42 and having arms43 and 44. The arm 43 has a cam shaped outer extremity which is locatedin registration with the lower side of the head 26 on the piston rod 23.A control member, such as a link 46, pivotally attached to the outer endof the arm 44 is provided for rotating the throttle '5 and bell crank41.

In operation, when the piston 22 is moved upwardly, the interior of thecylinder 18,the passage 28 and the interior of the valve housing 30 arefilled with fuel which is admitted through the inlet 19 of the cylinderand the drain passage 33 of the valve chamber 30. When the throttlevalve is openedlfrom a relatively closed position by clockwise rotationof the bell crank 41, the cam shaped extremity 45 of the arm 43 islowered, permitting the piston and piston rod 22 to be moved downwardlyby the spring 27. This action of the piston 22 displaces the fuel fromthe interior of the cylinder 18 and forces it through the passage 28 andinterior of the valve housing 30 under pressure. The ressure ofthe'fluid upon the shoulder 38 o the cylindrical enlar ement- 37 of thevalve 36 moves the latter ownwardly against the action of the spring 39,thereby lowering the valve from its seat 35 so as to permit the fuel tobe discharged from the pick-up sysburetor. at one end and with theinterior of a valve In the form shown in Fig. 2, the invention isillustrated in connection with a carburetor of the down-draft type whichhas a fuel reservoir 47 and a mixing chamber 48 in which a throttlevalve 49 is rotatably supported by a shaft 50. The reservoir 47 isprovided with fuel regulating apparatus including a float 51 andcoacting means, not shown, similar to the valve 8 shown in Fig. 1.

Formed in the reservoir 47 is a pump cylinder 52 in which a piston 53 isslidably mounted. Secured to the piston 53 is a piston rod 54 which isslidably mounted in an aperture of a boss 55 on the top wall of thereservoir 47. The cylinder 52 has a fuel inlet 56 communicating with theinterior of the reservoir 47 and having a valve seat 57 for receiving aball valve 58 and an outlet passage 59 which communicates with a valvechamber 60 formedin a boss 61 extending into the lower portion of thefuel reservoir.

The valve chamber 60 has an outlet 62 which is provided with a nozzle 63that extends into the mixing chamber 48 and has an outlet orifice 64.The outlet of the valve chamber has a valve seat 65 for receiving avalve 67 which is slidably mounted in the chamber. 60. Formed on theupper end of the valve 67 is a hollow cylindrical end portion or piston68 in which a spring 69 is mounted. The spring 69 bears at one endagainst the inner extremity of the cylindrical end portion 68, and atthe other and against a plug 70 that has a central aperture 71communicating with the interior of the reservoir 47 and is threaded inthe boss 61. The cylinder 52 and piston 53 form a pick up pump which isoperated by manipulation of the throttle through mechanism ineluding alever 72 on the throttle shaft 50 and a lever 73 pivoted at 74 on abracket 75 and connected to the lever 72 by a link 76. The freeextremity of the lever- 73 engages the lower side of a head 77 on thepiston rod 54 and holds the piston in its upper position against theaction of a spring 78 when the tiqhrotgle is relatively closed asillustrated in The pick-up system of a down draft carthrough the inlet56 thereof during the upward stroke of the piston, and forces thedisplaced fuel through the passage 59 and lower portion of the chamber60; The pressure of the fuel in the chamber acts upon the enlarged 5part 68 of the valve to raise the latter from its seat and permit thefuel to be discharged through the nozzle 63 into the mixing chamber 48.With the above construction, the fuel passage 59 and chamber 60 are atall times filled with fuel so that the pick-up shot commences to feedinto the mixing chamber 2 immediately upon the initial downward movementof the piston.

- In the form shown in Fig. 3, our improved 5 valve for controlling theoutlet of a pick-up system is illustrated in connection with acarburetor of the type shown in Fig. 2 and an intake manifold 79 ofstandard construction,

the parts of the carburetor of Fig. 3 being 39 numbered the same as thecorresponding parts of the carburetor shown in Fig. 2. The valvestructure includes a casing 80.having a chamber 81 therein and a nozzleart 82, extending into the intake manifold 9 and having outlet orifices83 for discharging fuel towards the respectively opposite ends of themanifold. Formed in the chamber 81 is a valve seat 84 against which avalve 85 is re leasably held by a spring 86. The valve 85 has anenlarged portion or piston 87 which is located slightly below a fuelinlet 88 formed in the casing 80. The fuel inlet 88 communicates withthe outlet 59 of the pump cylinder 52- through a conduit or pipe 89.Formed in the lower end of the valve casing 80 is a drain aperture 90which communicates with the interior of the-reservoir 74 through a pipe91.

With this form of our invention, the pickup system operates in themannerdescribed above but instead of introducing the pick-up shot intothe mixing chamber of the carburetor it discharges the same directlyinto the fuel mixture passage in the manifold of an engine. As manyvalve units of the type shown in Fig. 3 as desired, may be connected inparallel with the outlet 59 of the pump cylinder and installed so as todischarge fuel at various positions in the fuel mixture system of anengine. Valves of this type may be mounted on the cylinder head of anengine so as to introduce fuel directly into the cyl inders thereof.

In the form shown in Fig. 4 a diaphragm J valve is provided in place ofthe valve structure shown in Figs. 1, 2'and 3, for preventing thesuction of the fuel mixture system from draining the pick-up system. Thevalve includes a casing comprising detachable sections 92 and 93 betweenwhich'is mounted a dia hragm 94. get er by screws 95 and the uppersection 93 has a nipple 96 which is threaded in an aperture 97 of anintake manifold 98 and which has outlet orifices 99-communicating withthe interior of the manifold.

A conduit or pipe 100 communicates with the space between the uppersection 93 of the valve and the diaphragm 94 thereof at one end and withan outlet passage of a pick-up pump, not shown, but similar inconstruction to the pump illustrated in Figs. 1 and 2. Treadedin the endof the lower section 92 of the valve casing is an adjusting screw 101which engages a spring 102 that bears upon the lower central portion ofthe diaphragm 94 resiliently holding a valve 103, mounted on the upperside of the diaphragm, upon its seat 104. The interior of the pipe 100and the space above the diaphragm 94 are normally filled with fuel andas the pumpof the pickup system is operated the fuel above the diaphragm94 is placed under pressure. This action bulges the diaphragm downwardlyand removes the valve 103 from its seat. The fuel then flows into theinterior of the manifold through the orifices 99 from which it iscarried by the velocity of the fuel mixture system into the cylinders ofan engine.

In all the forms of our invention shown, the

fuel passage which leads from the pick-up pump is normally filled withfuel substantially to the discharge end of the system so that uponinitial movement of the piston of the pick-up pump, fuel is immediatelyfed into the fuel mixture system. This construction prevents the feedingof fuel by the pick-up system from excessivel lagging the opening of thethrottle valve f i'om its relatively closed position. The valvestructure is designed so that the vacuum of the fuel mixture systemnormally has a closing effect on the valve, thus sealing the outlet endof the pick-up system and preventing the vacuum from draining fueltherefrom when the pick-up pump is inoperative.

Although but several embodiments of this invention have herein beenshown and described, it will be understood that various changesincluding the size, shape and arrangement of parts may be made withoutdeparting from the spirit of our invention and it is our intention notto limit itsscope other than by the terms of the appended claims.

fuel mixture system of said engine, mechanism for intermittently feedingfuel through The sections are held to-' said passage under pressure, andmeans located at the discharge 'end of sald passage normally closing thesame and operableby the pressure of the fuel there1n fo'r opening saidpassage, said means tending to close said assage under the action of thesuction of sald fuel mixture system.

2." A pick-up system for an internalcombustion engine including meanshaving a fuel passage therein communicatrng with the fuel mixture systemof said engine, mechanism for intermittently feeding fuel through saidpassage under pressure, and a valve at the outlet end of said passagenormally closing the same and adapted to be opened by the pressure ofthe fuel in passage during operation of said mechanism, said valveopening in a reverse direction to the flow of fuel throug{ said passage.

v 3. A pic -up system for an mternal combustion engine including asource of fuel, means havlng a fuel passage therein communicating withsaid source of fuel and with the fuel mixture system of said engine,said passage being normally filled with fuel substantially to the outletend thereof, mechanism for intermittently feeding fuel through saidpassage under pressure, and a check valve in the outlet end of saidpassage for preventing draining of said passage by the suction in saidfuel mixture system betweenv operations of said mechanis I 4. A pick-upsystem for an 1nternal combustion engine including means having a fuelpassage therein communicatlng with the fuel mixture system of saidengine, mechanism for intermittently feeding fuel through said passageunder pressure, a valve seat at the outlet end of-said passage, and avalve in said passage normally tending to be held upon said seat by thesuctlon of sald fuel mixture system and operable by the pressure of thefuel in said passage for opening the latter when said mechanism isoperated.

5. In a carburetor including a fuel reservoir and having an air passage,a normal fuel system for feeding fuel into said air passage a pick-upsystem including a pump and having an auxiliary fuel passagecommumcating withsaid air passage independently of sand normal fuelsystem and with said pump, anda check valve in the outlet end of saidfuel passage, said valve being adapted to prevent discharging of fuelfrom said fuel passage and pump when the latter is inoperative.

6. In a carburetor having a fuel mixture passage, a fuel reservoir, apick-up system including a pump having a fuel inlet communi- V eatingwith said reservoir and an outlet passage communicating with said fuelmixture passage, a check valve in said fuel inlet, and means at thedischarge end of said outlet passage for sealing the latter against thevacuum in said fuel mixture passage when said pump is inoperative.

7. In a carburetor having a fuel mixture passage, a fuel reservoir, anormal fuel system forsupplyin fuel to said fuel mixture.passage, meansor temporarily feeding an auxiliary charge of fuel into said auxiliaryfuel mixture passage including a fuel passage, the

main portion of said fuel passage being below the fuel level of saidreservoir and normally filled with fuel to the outlet end thereof, and avalve in the outlet end of said auxiliary is inoperative.

8. In a carburetor having a fuel mixture passage for closing the samewhen said pump passage including a throttle valve, a fuel reservoir,means for temporarily feeding a charge of fuel into said fuel mixturepassage including a pump and having a fuel passage way communicatingwith said fuel mixture passage, the main portion of said fuel passagewaybeing normally filled with fuel by the head of fuel in said reservoir,a. valve in the outlet end of said passageway normally preventing thedraining of fuel therefrom by the suction in said fuel mixture passagewhen way communicating with said fuel mixture 7 passage, the mainportion of said fuel passageway being normally filled with fuel by thehead of fuel in said reservoir, a valve in the outlet end of saidpassageway normall preventing the draining of fuel therefrom by thesuction in said fuel mixture passage 7 when said pump is inoperative,means on said valve for moving the same in a direction substantiallyopposite to the flow of fuel through said passageway to an open positionby the pressure of the fuel in said passageway when said pump isactuated, and mechanism operable by variation of said throttle foractuating said pump.

10. In a carburetor having a body part including a fuel reservoir and afuel mixture passage, a pick-up system including a pump and having apassageway in said body part communicating with said pump and locatedbelow the fuel level of said reservoir, a valve housing in said bodypart having an inlet communicating with said passageway and an outletcommunicating with said fuel mixture passage, a valve in said housingfor normally closing said outlet and adapted to open in a directionopposite to the direction of suction in said fuel mixture'passage, and apiston on said valve for opening the same by the pressure to which thefuel in said housing is subjected when said pump is actuated.

11. In a carburetor having a fuel mixture passage including a throttlevalve, a main fuel system for supplying fuel to said fuel mixturepassage, a fuel reservoir, means for temporarily feeding a charge offuel into said fuel mixture passage including a pump and an auxiliarypassageway having an outlet communicating with said fuel mixture passageat an elevation above that of the fuel 10 level in said reservoir, themain portion of said auxiliary passage being normally filled with fuelby the head of fuel in said reservoir, and a check valve in the outletend portion of said auxiliary passageway located substan- 15 tially atthe elevation of the fuel level in said reservoir for sealing saidauxiliary passageway against the vacuum in said fuel mixture passageDERICK 0. BALL. 20 THOMAS M. BALL.

